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I'm still trying to get my head around this new encoder thing. This is still standard MPEG4, but more efficient? Does it put more of a load on the STB to decode as well? I'd think it'd have to, yet if it is still complying with the MPEG4 standard, presumably any MPEG4-rated STB should be able to decode it?

Which sort of makes me wonder if the rather thorough rewrite of the STB software might have been about more than just the UI. . . optimizing the mpeg4 decode path and providing more head-room for mpeg4 decode load?

So, is the consensus that with this new hardware there will really be no noticable difference in quality even when squeezing 6 HD channels in one transponder?

Yes.

So, it was stated above (unless I'm confused) that we have 30Mbps per transponder. Adding a 6th feed with bring us down to 5Mbps per feed... U-Verse level compression. If this is true, how does DirecTV plan to deliver the same channel, in the same bandwidth as U-Verse, but have no change in image quality?

So, it was stated above (unless I'm confused) that we have 30Mbps per transponder. Adding a 6th feed with bring us down to 5Mbps per feed... U-Verse level compression. If this is true, how does DirecTV plan to deliver the same channel, in the same bandwidth as U-Verse, but have no change in image quality?

Just relaying what we read in the Tandberg press release: "As part of a TANDBERG Television HD solution, the EN8190 encoder enables an additional HD channel per transponder for satellite operators when compared to alternative compression solutions."

Compressed bits and uncompressed bits don't have to turn out the same with different providers, depending on the quality of the hardware and software that compressed and uncompressed them. Your typical competitive bandwidth analysis assumes equality on that point. . . but it doesn't have to be so.

I'm still somewhat dubious, but apparently D* is already using it on a couple transponders, and I haven't yet seen any of DBSTalk's many, MANY IQ hawks raise any red flags yet. I feel pretty sure they would.

Compressed bits and uncompressed bits don't have to turn out the same, depending on the quality of the hardware and software that compressed and uncompressed them. Your typical competitive bandwidth analysis assumes equality on that point. . . but it doesn't have to be so.

I'm still somewhat dubious, but apparently D* is already using it on a couple transponders, and I haven't yet seen any of DBSTalk's many, MANY IQ hawks raise any red flags yet. I feel pretty sure they would.

In fact, there is a general consensus that AMCHD got noticeably better a little while back, some months post-launch on D*. Dunno if it is related.

I still think there'd have to be extra load on the STBs too. Whether that be more processing cycles, or more memory usage for mpeg4 decode, or both. Which makes me wonder if the STB client rewrite was also an enabling, moving part here.

In fact, there is a general consensus that AMCHD got noticeably better a little while back, some months post-launch on D*. Dunno if it is related.

I still think there'd have to be extra load on the STBs too. Whether that be more processing cycles, or more memory usage for mpeg4 decode, or both. Which makes me wonder if the STB client rewrite was also an enabling, moving part here.

Hey, I've got a back log of Mad Men eps going back to January so I should be able to make that comparison. Though it'll likely spoil something for me LOL.

Maybe I can find a rerun of one the older eps to compare with my older ones.

EDIT: Ha, there's and upcoming rerun of the ep "Maidenform" for which I have a pre E! HD recording of. Of course there's really no way to know at what point they reconfigured the enconders in anticipation of adding E! HD

I'm not trying to say the sky is falling, and PQ will be terrible. I've not noticed any major change. I noticed a couple days ago while watching HGTV that it appeared slightly grainy, but I'm sure that was an HGTV problem.

I mostly just wonder how D* can stream 5Mbps HD streams and them look so good compared to the VERY obviously bit starved U-Verse streams that are 5-6Mbps. I compare them directly due to AT&T being the provider I left when I switched to DirecTV.

I have no way of proving one way or another, I based that completely off the info posted above.... but what you are saying is exactly what I was trying to say. IF it really is 30Mbps / 6 streams = 5Mpbs per stream, and it still look great, then I'm sure every provider would want those magical encoders!

I'm not trying to say the sky is falling, and PQ will be terrible. I've not noticed any major change. I noticed a couple days ago while watching HGTV that it appeared slightly grainy, but I'm sure that was an HGTV problem.

I mostly just wonder how D* can stream 5Mbps HD streams and them look so good compared to the VERY obviously bit starved U-Verse streams that are 5-6Mbps. I compare them directly due to AT&T being the provider I left when I switched to DirecTV.

Directv does not have the HD streams limits. Also I think that 1 satellite transponder has the same bandwidth that att has for the link to each house to put TV + HSI over.

So in the Portland, OR DMA, we've had 7 channels on one transponder (103(s) tpn 21) since I started checking the tpn maps 3-4 years ago. We added another one a month or two ago for 8 active channels with a 9th in test. So, that's 9 HD channels on one tpn!

I guessing they are using different modulation for those spot beams to gain some bandwidth but I would think they have to be using better encoders to fit 9 channels in there. Also, I see no perceivable difference in PQ between SAT delivered locals and the OTA version through my AM21.

Interesting observation from the presentation --it does better (savings-wise vs previous generations) with 720p and "complex material". To me, the classic example of "complex" is fast moving sports where a large portion of the screen is always in motion.

The flip side of that is that even with an unlimited budget to upgrade (not likely!), their mix of channels might (probably?) limits them to something less than getting a full 44 worth of HD channels extra bandwidth in this manner. Of course, I'd settle for another 10-15 pretty happily.

There are many factors that can go into PQ other than bandwidth. Consider it like horsepower. The more you have will make things better but there are also ways to make something just as good with less by being more efficient or having new technology go in. Better encoding, less error correction bandwidth needed, new algorithms to make it faster to decode all of this can get tied in.

Dish Network has some tpn's with 7 or 8 HD's on it. I'm pretty sure those occur on Ku band satellites and they also use turbo fec and 8psk modulation. Since Ku is less susceptible to rain fade they can lighten up on forward error correction and use more robust modulation schemes to get better throughput per transponder. Were talking 60-70mbps per transponder. If DirecTV had the luxury of using Ku for its newest birds, they could of used more efficient modulation and error correction too.

On cable where they have 6 MHz "channels" to deal with, a 256QAM channel yields 38.8mbps usable data rate. In the past few years improvements in encoder design allowed them to go from 2 HD's to 3 HD's per QAM. That's 12.93 mbps but keep in mind that is MPEG2 still. AMC networks goes one step further and packages 4 HD channels in MPEG2 to fit in one QAM (9.7 mbps for AMC, Fuse, IFC, We HD) (Galaxy 14 tp2).